Various apparatus have been developed to assist in moving, transporting and/or lifting a patient, invalid or other incapacitated person, herein generally referred to as a "patient". Many of the known apparatus have been highly specialized with respect to functional capabilities. For example, many known lifting apparatus are constructed to function primarily for lifting of a patient, and as such often involve some type of boom from which a patient can be suspended in a harness or the like to carry out the lifting function. The general apparatus of this type, however, are generally suitable solely for such lifting function and hence are not suitable for general transporting functions.
Rather, a general transporting function for patients is normally carried out using wheelchairs or like devices. Numerous wheelchairs have been developed for this purpose, including both motorized and manually propelled wheelchairs. Again, however, most wheelchairs are limited with respect to functional capabilities in that they typically provide only mobility or transportability from one location to another, and are unable to successfully perform other necessary functions, such as assisting in patient transfer, lifting and the like.
One attempt to provide a wheelchair of improved functional capability is illustrated in my U.S. Pat. No. 5,112,076. This latter patent illustrates therein an improved wheelchair which is believed highly desirable with respect to the capability to not only provide significant mobility in terms of transporting a patient from one location to another, but also provides significantly improved performance with respect to facilitating lifting and lowering of a patient seated in the wheelchair, and transferring of the patient from or to the wheelchair, such as between the wheelchair and a bed, due to the features of the seat assembly and its ability to be readily disconnected from the chair and positioned on a bed.
Another attempt to provide for improved performance capability of a patient transporting device is illustrated in U.S. Pat. No. 4,255,823 which illustrates a transporter which functions as a wheelchair. The wheelchair includes a seat assembly which can be raised and lowered and which can also be converted to lay generally flat so as to function as a stretcher. In the device of this latter publication, however, the entire seat assembly is pivotally supported in a cantilevered fashion solely at a single pivotal connection disposed at one side of the seat assembly substantially at the hinge between the seat and back, which hinged connection itself is provided on the free end of a single vertically-swingable support arm which controls movement of the seat assembly. This creates structural problems in terms of strength and stability due to the cantilevered support of the seat assembly. Further, when the seat assembly is folded horizontally into a stretcher position, the support of the stretcher as provided by the cantilevered connection between the arm and the hinge point between the seat and back results in a significant portion of the stretcher being cantilevered outwardly a significant distance beyond the wheels which support the base, and in fact the center of gravity of the patient is no longer centered generally over the base but is positioned rather precariously adjacent one side of the base, which can cause undesired instability and potential tipping.
Accordingly, it is an object of this invention to provide an improved patient transporting device which is capable of functioning as a wheelchair, as a patient lifting and transfer device, and as a stretcher, and which overcomes disadvantages associated with prior devices as briefly explained above.
More specifically, this invention relates to an improved patient transporting device which is constructed similar to and functions in the manner of a wheelchair, and which is constructed similar to and incorporates numerous advantages associated with the wheelchair of my aforesaid U.S. Pat. No. 5,112,076. In the improved device of this invention, however, the seat assembly can also be readily converted, while mounted on the frame of the device, so as to function as a stretcher. The conversion of the seat assembly into a stretcher can be readily and safely accomplished by an assistant and, when the seat assembly is converted into a stretcher, the support of the seat assembly is such as to enable the seat to be shifted forwardly relative to the base as the back is folded down to maintain the center of gravity of the patient, when disposed on the stretcher, more centrally located over the base to maintain desired stability of the device.
This invention also relates to an improved patient transporter which functions as a wheelchair and can be readily used in conjunction with a standard toilet.
Other objects and purposes of the invention will be apparent to persons familiar with devices of this general type upon reading the following specification and inspecting the accompanying drawings.